Mining methane, sequestering carbon dioxide and farming in oceans

ABSTRACT

The present invention is a multiple purposed system of producing methane from its hydrates and sequestering carbon dioxide into its hydrates. Methane hydrates mixed with mud, prepared with methane mining assembly  23  are brought to sea surface by a series of buckets  16  attaching to rotating chains  18 . The decomposed methane is collected into the methane dome  50  and is processed into liquefied natural gas or synthetic liquid fuels. Liquid carbon dioxide is brought down through a tube  70  and a sequestering device  86  into the sea where the pressure and the temperature are adequate for carbon dioxide hydrates to form and settle down to the sea bottom. The unconverted gaseous carbon dioxide is collected into carbon dioxide dome  49  and is liquefied again for recycling. A specially designed marine plantation, comprising of plurality of planting units  352  and a fleet of seeding and harvesting boats, is employed to remove the residual carbon dioxide from the sequestering, to alleviate the global warming, to serves as an abundant source of renewable energy, and as a huge sink for carbon. In addition, it could provide a profusion of less-polluted seafood. The operations of mining methane, sequestering carbon dioxide and marine plantation are fully integrated and optimized

This application claims the benefit of provisional patent application Ser. No. 60/849,392 filed by the present inventor on Oct. 5, 2006.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention relates to the using of fleets of specially designed ships and boats on: (1) mining methane from methane hydrates, (2) alleviating global warming by sequestering carbon dioxide, fast growing of vegetables, and promoting the proliferation of diatoms; (3) harvesting renewable energies from sea-growing biomass, wind, sun, and (4) producing sea foods profusely.

2. Prior Art

Human beings are suffering from: (1) the lack of cheap and convenient energy source, (2) the annually discharging of 29 billon tons of anthropologic carbon dioxide worldwide into the atmosphere to cause global warming, and (3) the insufficiency of foods to feed the poor. In the past few years, the oil price has increased threefold and it hovered between $60 and $70 a barrel for while and now it is above $70. The U.S. is consuming petroleum at the rate of around 21 million barrels a day. About 60% of them is imported, mainly from Middle East and Venezuela. Both of these regions are politically unstable. Although efforts are carried out to substitute part of it by agricultural product, alcohol, but it has many other problems.

A majority of the world's climatologists and scientists (more than two thousand strong) consider global warming real, but a minority of them still take a dubious or even opposite attitude. The situation becomes worse by the deforestation through land development and the ocean's decreasing ability to assimilate carbon dioxide. On the other hand, oceans cover more than ⅔ of the global surface, and they are virtually untapped. They may offer an excellent opportunity to alleviate the global warming problem.

In recent years, methane hydrates have been found to occur worldwide, from Japan to New Jersey and from Oregon to Costa Rica, in enormous quantities. Most experts agree that marine methane hydrates collectively harbor twice as much carbon as do all known deposits of natural gas, crude oil and coal on the earth. The energy stores in methane hydrates could be the potential fuel for our energy hungry world in the twenty first century if practical mining techniques were devised.

It is well known that carbon dioxide can react with water to form carbon dioxide hydrates. They are very stable on the sea-bed where the pressure is enormous and the temperature is close to zero. Sea bottoms may serve as inexhaustible burying grounds for anthropologic carbon dioxide, if technical and economical means could be developed.

If the area of open-sea plantation is of vast scale, oceans can be an enormous source of renewable energy and abundant sea food.

Prior arts exist for all those three categories: 1. methane from methane hydrates, 2. carbon dioxide sequestering and marine farming.

Category 1, Methane from Methane Hydrates:

U.S. Pat. No. 4,424,866 (1984) to Patrick L. McGuire taught the pumping of hot CaCl₂ solution down to methane-hydrates formation to recover methane gas. It has the disadvantages of possible leaking methane into atmosphere, and the pollution of environment by using large quantity of chemical. It also incurs a high cost.

U.S. Pat. No. 6,733,573 (2004) to Lyon taught the use of acidic catalyst to speed up the reactions of decomposition of methane hydrates and the formation of carbon dioxide. It has the risks of escaping liberated methane and unconverted carbon dioxide into the atmosphere and polluting the environment by employing large quantity of acids.

U.S. Pat. No. 6,978,837 (2005) to Yemington taught the use of heat from multiple sources (including combustion in situs) to decompose methane hydrates, followed by collecting the liberated methane. The building of heat supplying device in methane-hydrate formation and methane-collecting system on top of the formation are extremely difficult, because the sites are located at least 1,500 ft. to several miles from sea-surface. There is no light and the pressure is enormously high there. It will be even more difficult when methane hydrates at one location are exhausted and relocation is needed. The high cost of heat is another problem.

US Patent Applications 20050284628 (2005) by Pfefferle teaches a method of decomposition of methane hydrates by supplying a fuel and an oxidizer to methane-hydrate deposit introducing a combustion in situs. Again, to bring fuel and oxidizer to methane-hydrate formation is difficult, and the costs of fuel and oxidizer are high.

US Patent Application 20060032637 (2006) by Ayoub et al teaches the use of hot water from neighboring aquifer to melt methane hydrates. This method has a number of difficulties including 1) the neighboring aquifer with high temperature is not easy to come by and 2) it is difficult to control the flows of aquifer water and the produced methane at the ocean bottom.

US Patent Application 20050252656 (2005) by James Q. Mcguire teaches the production of oil from oil shale and methane from methane hydrates by injecting liquefied gases to fracture the drilled hole and supplying heat. However, supplying heat into the fracture is difficult and costly.

US Patent Application 20050120878 (2005) by Leppin et al and US Patent Application 20050121200 (2005) by Alwarappa Sivaraman teach a method of using carbon dioxide to liberate methane from methane hydrates by means of so called “hydrates exchange reaction”. Gaseous carbon dioxide is injected into subterraneous methane hydrates field, as a result, the formation of carbon-dioxide hydrates liberates methane from methane hydrates. However, the exchanging reaction is rather slow. This teaching has no means to prevent the leaking of unconverted carbon dioxide and the liberated methane into the environment.

Category 2, Carbon Dioxide Sequestration

U.S. Pat. No. 5,364,611 (1994) to Tijima et al taught the fixation of carbon dioxide by bringing it down deep into the sea. It incorrectly assumed that the conversion will be complete, and the leaking of unconverted carbon dioxide back to the atmosphere will be real.

U.S. Pat. No. 6,890,497 (2005) to Rau et al taught a method of sequestering carbon dioxide by reacting dissolved carbon dioxide with carbonate. The use of large quantity of chemical may pollute the environment.

U.S. Pat. No. 5,397,553 (1995) to Spencer taught the sequestering of carbon dioxide by sub-cooling both carbon dioxide and water to form hydrates with no means to collect the un-reacted carbon dioxide.

U.S. Pat. No. 6,190,301 (2001) to Murray et al taught the embedding of solid carbon dioxide in sea-floor sediment. Although, with the help of a heavy weight, the downward speed of the torpedo-shaped solid carbon dioxide (SCD) is very fast, the temperature difference between SCD and its surrounding water near sea-surface may be close to 100° F. Such high temperature difference may melt or evaporate a part of the SCD. Thus, it will increase the cost of implementation and the risk of pollution.

US patent Application 20010002983 (2001) by Michael Markels Jr. teaches the method of sequestering of carbon dioxide with a fertilizer comprising chelated iron. It has no means provided for collecting the un-converted carbon dioxide. In addition, the use of chemicals increases the cost.

U.S. Pat. No. 6,598,407 (2003) to West et al taught the efficient injection of liquid carbon dioxide into sea, 700 meters or deeper, then it is mixed with cold marine water there. It has no provision to collect or recycle the portion that was not sequestered.

Tanaka et al (15) discussed the disposal of carbon dioxide by enhanced oil recovery (EOR). Limited number of oil wells suitable for EOR, cost of carbon dioxide transportation and leaking of carbon dioxide from the oil field, and the possibility of tragedy similar to the killing of thousands people in Cameroon some time ago, can limit the widespread use of EOR.

US Patent Application 20070028848 (2007) by Lutz teaches the method of sequestering carbon dioxide in aqueous environment. It provides no means to collect and recycle the un-sequestered carbon dioxide.

Herzog et al (3), Rau et al (4), Baes et al (5), Steinberg et al (6), Herzog (7), Morgan et al (8), Hirai et al (9), Yamasaki et al (10), Ballard et al (12), Austvik (13), and Jones et al (14, 15) have all discussed the collection and sequestering of carbon dioxide in water or oceans. However, no practical and economical approach has been suggested.

Category 3, Marine Farming

U.S. Pat. No. 5,397,553 (1955) to Spencer taught the construction of submerged platform structure for open sea farming. Despite that it is relatively transparent to the forces of waves, no other advantages with regard to farming and harvesting were mentioned. Furthermore, there is no anchor to the sea-bottom to fix the system at one place.

U.S. Pat. No. 4,872,782 (1998), U.S. Pat. No. 4,950,104 (1990), U.S. Pat. No. 5,884,585 (1999) and U.S. Pat. No. 6,325,569 (2001) to Streichenerger taught the use of artificial habitats to enhance the biological-mass production, and kelp-mussel cultivating. These operations are only limited to shallow sea-bottoms.

U.S. Pat. No. 5,309,672 (1990) to Spencer et al taught a method of submerged platform structure for open macro-algal farming. Despite that it is relatively transparent to wave motion, no other advantages with regard to farming and harvesting is were mentioned.

U.S. Pat. No. 6,056,919 (2000) to Markels taught the sequestration of carbon dioxide by photo-plankton photosynthesis. This method lacks the additional advantages enjoyed by the present invention such as the harvest of biological fuels and fish.

US Patent Application 20070028849 (2007) by Kvietelaitis teaches the use of an aquaculture device to cultivate shellfish such as mussels. It provides no means to raise fast growing plants to absorb carbon dioxide.

3. Objects and Advantages

Accordingly, besides the objects and advantages of the application of the specially designed and constructed ships and boats in mining methane, sequestering carbon dioxide and farming in oceans described in my above patent, several other objects and advantages of the present invention are:

(a) to provide a system of equipment to mine methane by bring its hydrates (mixed with mud) from sea-bed to sea-surface enabling them to decompose naturally without the use of any heat or chemical.

(b) to provide a means to collect the decomposed methane for further purification, liquefaction and refining to liquid fuels by conventional means.

(c) to provide a system for sequestering carbon dioxide by bringing it, in liquid form, down to deep enough marine water where the pressure is high enough and the temperature is low enough for the formation of carbon-dioxide hydrates, which settle down to bottom of the sea. Not any chemical is needed. This approach is much simpler and economical than prior arts.

(d) to provide a device to collect the gaseous carbon dioxide, that has not been sequestered, for recompression and recycling.

(e) to provide a marine plantation to absorb the liquid and dissolved carbon dioxide that has escaped the sequestering operation.

(f) to provide a system for cultivate fast growing vegetables, such as kelp or seaweed, which is in turn harvested as a renewable energy source.

(g) to provide a system for the production of sea food.

(h) to provide services for seeding, fertilizing and harvesting of fast growing vegetables, and sea foods.

(i) to provide services for fostering the proliferation of diatoms to absorb carbon dioxide from atmosphere. Since this operation is for the good of whole mankind, it should under the supervision of The United Nation and the latter should bear the cost.

(j) to provide a observation station to let tourists telescoping rarely-seen-new lives on deep-sea bottoms. Admission charges will deplete part of the overall cost of the whole endeavor supported by the present invention.

(k) to provide a platform for exploration of renewable energies such as wind, and solar powers.

(l) to provide a plenty of opportunity to internal mutual cooperation and optimization to minimize the overall cost and maximize the total profit of the whole endeavor supported by the present invention. It may mushroom to an important industry.

(m) to provide a new frontier of decent existence for mankind.

(n) to provide an abundant seafood supply. Many varieties of fish became scarce after many years of over fishing. The plantation units can serve as safety habitats for under-sea lives, they would be prosperous again. Since these plantation units are located far away from coast lines and river estuaries, these sea animals are much less polluted by mercury and other poisonous materials. These less polluted seafood can enrich the diets of hungry people of the world.

The further objects are to help ocean-neighboring countries such as The United States, Japan, China and Taiwan, etc., to be independent of foreign oil and lowering the world's demand of Mid-East's oil and improving peace in that region.

SUMMARY

In accordance with present invention a fleet of specially designed ships and boats is used to engage in mining methane from its hydrates, sequestering carbon dioxide and farming in oceans.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, closely related figures have the same number but different alphabetic suffixes.

FIG. 1 shows the pressure vs. temperature diagram for methane-water system.

FIG. 2 shows the pressure vs. temperature diagram for carbon dioxide-water system.

FIG. 3 shows vertical temperature distributions of marine water at various locations.

FIG. 4 shows the installation for mining methane from its hydrates.

FIG. 4A shows the inserting to and removing a chain section from the chain loop.

FIG. 5A shows the front view of the rotor-channel system for the moving chains in methane mining assembly.

FIG. 5B shows the side view of the rotor-channel system for the moving chains in methane mining assembly.

FIG. 6 (at the center of Page 4/14) shows the carbon dioxide sequestering installation.

FIG. 6A (at middle left corner of Page 5/14) shows the control of liquid carbon dioxide flows.

FIG. 6B (at middle right corner of Page 5/14) shows the concentric tube for the transportation carbon dioxide.

FIG. 6C (at lower left corner of Page 5/14) shows the hollow center motor.

FIG. 6D (at the lower right corner of Page 5/14) shows the refrigerating radiator

FIG. 6E (at the top left corner of Page 5/14) shows the front view of liquid carbon dioxide nozzles.

FIG. 6F (at the top right corner of P. 5/14) shows the top view of liquid carbon dioxide nozzles.

FIG. 7A shows the walking mechanism in retired condition.

FIG. 7B shows the walking mechanism in operating condition.

FIG. 8A shows the bottom view of methane mining assembly.

FIG. 8B shows the connecting end of a chain.

FIG. 8C shows the side view of walking device.

FIG. 8D shows the pegging device.

FIG. 8E shows the hydraulic system of chain driving.

FIG. 9 shows the front view of the plantation unit.

FIG. 10A shows the top view of a seeding and harvesting boat.

FIG. 10B shows the side view of a seeding and harvesting boat.

FIG. 10C. shows the boat is in seeding or harvesting operation.

FIG. 11 shows the top view (under the ship roof) of a ship for mining and sequestering.

FIG. 12 shows the automatic tension control of the chain loops.

FIG. 13 shows the back sectional view of a mining-sequestering ship.

FIG. 14 shows the recycling of carbon dioxide.

FIG. 15 shows the arrangement of sea plantation units.

DRAWINGS-Reference Numerals

10 chain-loop driving drum 12 auxiliary driving drum 14 float 16 bucket 17 one section of chain loop 18 chain loop 19 driving sprockets on the drum 12 20 driving sprockets on the drum 10 22 Frame of methane mining device 23 methane mining assembly 24 stirrer with motor 26 motor driving the grinder 28 grinder 30 methane hydrate formation 32 power cable 34 chain supporting rollers 36 power cable driving drum 38 gloves 40 transparent windows on dome 46 ocean depth 48 channels for rollers 49 carbon dioxide collecting dome 50 methane collecting doom 51 sea level 52 ship bottom 54 chain supporting rollers (FIG. 5 A& B) 56 channels for roller (FIG. 5 A&B) 58 top of mining assembly 60 width of bucket 62 depth of mud bucket 64 compound-cord-driving drum 66 compound cord 68 power cable for sequesterer 69 chain supporting sequesterer 70 concentric carbon dioxide tubing 71 weight supporting stainless steel tube 74 valve box 76 upper agitator with motor 77 hollow center motor 78 liquid carbon dioxide jets 80 refrigerating radiator 82 & 84 lower agitator and its motor 86 sequestering assembly 88 carbon dioxide exit from radiator 90 carbon dioxide entrance into radiator 94 radiator fins 92 carbon dioxide flow from lower to upper chamber in the refrigeration radiator 96 carbon dioxide flow to be sequestered 98 carbon dioxide flow as refrigerant 99 windows on carbon dioxide dome 100 carbon dioxide gas from the radiator 101 carbon dioxide to recycling system 102 purging gas 103 pure carbon dioxide into the dome 105 fresh air into the dome 104 central space of the concentric tube 106 annular space of concentric tube 114 temperature controller for flow 96 115 temperature controller for flow 98 116 male screwed rod 118 pair of gears 120 driving motor 122 female screwed rod 124 walking device 126 base of methane mining assembly 127 drum support bearings 129 drum driving motor 130 piston of drum support 132 connecting end of a chain 134 usual chain ring 135 motor 136 connecting opening 137 gear pair 138 stainless steel spring 139 male screw 140 rivets 141 female screw 142 cylinders of drum support 143 sharp tip of locking peg 144 hydraulic fluid reservoir 145 wedge to prevent rotation of 141 146 two way pump 148 pump driving motor 150 signal or location buoy 152 harvest indicating buoy 154 main nylon core line 156 auxiliary-connecting-nylon line 158 ring-and-hook link 160 plastic pipe 161 inter-pan connecting line 162 mixture of gravel and fertilizer packs 171 inflation valve 172 anchoring weight 174 height of plantation tower 176 depth of the sea 178 circular hole to adapt plantation unit 180 seeding-harvesting platform 182 hoists 184 farming pan storage 186 tool storage 188 fish collector 190 shell fish collector 194 centrifuge 196 dryer 198 dried kelp or seaweed 200, 202 general storages 204 battery compartment 206 liquid carbon dioxide storage 208 fertilizer solution storage 210 liquid carbon dioxide dispenser 212 fertilizer solution dispenser 214 electric-gasoline dual engine 216 transmission 218 marine propeller 220 piloting cabinet 221 anchor port 224 entrance to lower decks of ship 226 carbon dioxide colleting domes 228 methane colleting domes 300 synthetic gasoline plant 302 methane liquefaction plant 304 bucket or chain storages 306 control board for whole ship 308 carbon dioxide recompression plant 310 crew living quarters 320 tension indicator 322 three mode tension controller 324 liquid carbon dioxide storages 326 liquefied methane storages 328 gasoline or liquid fuel storages 330 storage batteries 332 wind power generator 324 solar panels 336 methane stream 338 tail gas from liquid fuel plant 340 two cycle gas turbine 342 electrical power generator 344 carbon dioxide compressor 346 carbon dioxide cooler 348 liquid carbon dioxide to sequestering device 350 carbon dioxide from collecting dome 352 plantation units

DETAILED DESCRIPTION A FIGS. 1, 2 and 3 Scientific Bases of the Present Invention

Scientists Roberts et al (1940), Jhaveri et al (1940), Jhaveri et al (1965) Galloway (1970), Deaton et al (1946), Mclead et al (1961), Verm (1974), De Roo et al (1983), Thakore et al (1987), Adisamito (1991), and Ballard et al (2001) have established that methane can combine with water to form methane hydrates under high pressure and low temperature. FIG. 1 shows the pressure-temperature diagram for methane-water system, and the temperature is in an ordinary scale but the pressure is in a logarithmic scale. If methane hydrates lie anywhere in the region above the straight line, they will be stable.

Austvik et al (13) has studied the pressure-temperature equilibrium diagram for carbon dioxide and water system. Study results are shown in FIG. 2. Both pressure and temperature are plotted in ordinary scales. Carbon dioxide hydrates lie anywhere in the region above the curve will stay stable.

FIG. 3 (U.S. Pat. No. 5,364,611) shows the vertical temperature distribution of marine water at various locations. If the sea bottom is deep enough, its temperature is always close to or few degrees above zero. This means that if an ocean is more than 1500 feet deep, it can keep both methane hydrates and carbon dioxide hydrates there permanently. If the ocean bottom is between 500 to 1500 ft., it may only keep carbon dioxide hydrates stable.

From the above discussion, if ships can meet all the technical and managerial requirements suggested by the present invention, they can be employed to mine methane from methane hydrates, and to sequester carbon dioxide and deposit it in the ocean bottoms.

In the case of mining methane, the ships are equipped to dig loose the hydrates from the formation at the sea bottom and bring them to the surface. Being subjected to the atmospheric pressure and warmer temperature at the surface of the sea, methane hydrates decompose automatically. The ships provide a means to collect the decomposed methane effectively, preventing it from polluting the environment. No heat or chemical is needed. Any physical construction in the hydrate formation is completely avoided.

In the case of carbon dioxide sequestering, liquid carbon dioxide is pumped down marine water to a depth of 1000 ft. or more. The deeper the better. However, for economic reasons, it doesn't have to reach the bottom of the sea. Due to the fact that the density of carbon-dioxide hydrate is heavier than that of marine water, once formed, it will settled down to the bottom of sea. They stay there forever if without outside disturbance.

However, we do not expect that the sequestering reaction to reach completion. The ships have a means to collect effectively the un-reacted gaseous carbon dioxide. In addition, a system of marine plantation is provided to absorb the un-reacted liquid and dissolved carbon dioxide. Besides the prevention of escaping carbon dioxide into the environment, the plantation brings numerous other advantages, such as reaping various renewable energies and harvesting bumper crop of virtually pollution free sea food.

DETAILED DESCRIPTION B FIG. 4, FIG. 5A, FIG. 5B, FIG. 7A, FIG. 7B, FIG. 8A, FIG. 8B, FIG. 8C, FIG. 8D, FIG. 8E and FIG. 12 Preferred Embodiment for the Mining of Methane

A preferred embodiment of the methane mining installation of the present invention is illustrated in FIG. 4. The methane mining consists of a chain driving rotating drum 10, an auxiliary rotating drum 12, a pair of rotating chains 18, a methane mining assembly 23, a methane collecting dome 50, and a methane purification unit (not shown). The methane mining assembly 23 further includes of a grinder 28, a hanging frame 22, which is rested on a set of rollers 34, a motor 26 and a stirrer 24. During mining, grinder 28 is in touch with the methane hydrate formation 30. The power running the mining operation comes from the electrical cable 32. Along the whole length of the rotating chain 18, methane-hydrate-lifting buckets 16 are attached to it at equal distances. Each bucket holds one or several floats 14 to neutralize the weights of the bucket, its contents and that of the chains.

Dome 50 has a cylindrical wall and a semi-spherical top. Around the wall, there are several transparent windows and about half a dozen flexible gloves 38 on the dome to allow workers outside the dome to manipulate the machinery inside the dome.

The water column formed between the water surface in the dome (the same as outside sea level) and the ship bottom 52 serves as a seal to separate pure methane from the air outside the ship. The sea surface is 51. The depth of the sea is 46. The produced methane leaving dome 50 first passes through a purifier system (not shown) mainly to remove carbon dioxide as an impurity, then it branches into liquefied natural gas plant 42 and liquid fuel synthesis plant 44.

As shown in FIG. 5A and FIG. 5B the methane mining assembly is hanging on the pair of rotating chains 18 through groups (one on each side) of rollers ‘34 or 54 ’ that are housed in a semi circular channel, 48 or 56. Each roller can rotate freely around its axis which is fixed on each inside of the wall of the channel. The hanging frame of the methane mining assembly 22 with a top 58 is attached to the roller channel 56. The methane mining assembly 23 and the roller channel 56 are connecting together through welding or riveting. During mining, the chain loop moves down on the right side and upward on the left bringing up the buckets which are hanging on the chains. During the downward movement of the left branch of rotating chain, all the buckets attached to it are facing downward. When the bucket passes underneath the roller-channel combination, the mouth of the bucket is facing horizontally toward left and it collects the mud containing methane hydrates which is being brought up from the sea bottom by the actions of the grinder 28 and the stirrer 24 (see FIG. 4 and FIG. 5A and FIG. 5B). The whole methane mining assembly 23 together with the roller-channel combination of 54 and 56 are riding on the rotating chains. When the chains rotate, the rollers also rotate freely about their axes, but the methane-mining assembly together with the roller-channel combination stay stationary on the bottom of the sea.

FIGS. 7A and 7B illustrate the walking mechanism which is attached to the methane mining assembly 23 (see FIG. 4). The walking mechanism can be moved up or dawn by a pair of motors 120 (one on each side), a pair of gears 118, two female screwed rods 122, and two male screwed rod 116. Because female screw rod 122 is prevented from rotating, it can only move vertically; and 116 is prevented from vertical movement, it can only rotate. Therefore, when the male screwed rod 116 rotates clockwise or counterclockwise, it makes the female screwed rod 122 move up or down, as does the walking device 124. FIG. 7A shows the walking mechanism in retired position and FIG. 7B shows it in working condition.

FIG. 8A shows the bottom of the frame 22. Frame 22 houses the methane-mining assembly 23 (see FIG. 4). At the four corners of base 126, there are four pegs in their top views. The grinder 28 is driven by motor 26. 128 is the collecting space for hydrate-mud mixture. 139 is a male screwed rod and 141 is a female screwed rod. 145 is a wedge which allows it only to move vertically and prevents it from rotating. The walking mechanism 124 is also attached to base 126. FIG. 8D shows the front view of a locking peg which has a sharp pointed tip 143. 135 is a motor. 137 is a pair of gear. 139 is a male screw and 141 is the peg with a female screw inside. 145 is a wedge which prevents the rotation of the peg 143 which has a shape tip. FIG. 8B shows the connecting end of a chain section. 132 is the end ring of a connecting end. 138 is a stainless spring which allows a normal chain ring to go in and doesn't allow it to come out unless using a hand or a special device. 136 is the opening of the end ring. 140's are rivets which fixes the spring to the end ring.

FIG. 8E shows the hydraulic systems used to move up or down the main driven drum 10 or the auxiliary driven drum 12. 130 are pair of plungers which move in and out a pair of tightly fit cylinders 142 which are fixed to the ship body. 144 is a hydraulic fluid reservoir. Pump 146, driven by a motor 148, can bring the hydraulic fluid form reservoir to cylinders and vice versa.

In order to avoid the daily tide movement to interfere with the smooth methane-mining operation, an automatic control system is designed as shown in FIG. 12. During mining of methane hydrates, low tide may slacken the rotating chains and in turn disturb the mud collecting buckets. On the other hand, high tide may beak the pins on the driving drum 10. To synchronize the mining operation with the daily tide movement, a tension indicator 320 is inserted between the methane mining assembly 23 and the ship.

After the tension indicator is set on a desired value, when there is positive deviation, +e, it sends a signal to the tension controller 322, which in turn instructs the pump 146 to transfer an adequate amount of hydraulic fluid from the cylinder 140 to the reservoir 144 in order to maintain a constant tension in chain loops 18.

DETAILED DESCRIPTION C FIG. 6, FIG. 6A, FIG. 6B, FIG. 6C and FIG. 6D Preferred Embodiment for Carbon Dioxide Sequestering

FIG. 6 shows the equipment for the sequestering of carbon dioxide which is housed in carbon-dioxide collecting dome 49 with a semicircle top and a cylindrical body. The equipment consists of a composite cable 66 which is encircled around a cylindrical hoist 64 and a sequestering device 86. The composite cable is made up of a stainless metallic chain 69, to sustain the weight of the sequestering device; an electric cord 68, to supply electricity to the motors; and a concentric, carbon-fiber reinforced, flexible tube 70 to feed liquid carbon-dioxide to dispensers or the carbon-dioxide jets 78, and return expanded carbon dioxide from the radiator 80 back to recompression, through the annular space The sequestering device 86 consists of a valve box 74, two motor-agitator pairs 77-76 and 84-82 and a refrigerating radiator sandwiched between them. The two motors driving the two agitators are attached to a rigid stainless tube 71 to endure the torque produced by the two agitators which are rotating at the opposite directions. On the walls of the dome, there are group of observation windows 99. On top of the dome, a group of pipe lines are provided to supply and remove air or carbon dioxide.

FIG. 6A shows the content of the valve box 74. High pressured liquid carbon dioxide comes from the center of the concentric tube 104 (see FIG. 6B). It branches out to two streams. Stream 96 discharges at 78 where carbon dioxide is to be sequestered. Another stream 98 goes to the radiator 80 and serves as a refrigerant. Two temperature controlled valves 114 and 115 are utilized to prevent the down streams from being frozen to solids.

FIG. 6D shows the detail of the radiator. Liquid carbon dioxide from stream 98 (see FIG. 6A) enters the radiator's lower chamber through the entrance 90. It then passes through orifices 92 into the radiator's upper chamber, and leaves the exit 88 back to the annular space 106 (see FIG. 6B), transferring back to the ship for recycling.

FIG. 6C shows the hollow center motor 77 which drives the upper agitator 78. The chain 69 through the hollow center is to support the weights of the radiator 80 and motor agitator pair 82-84. The electric cable 68 through the hollow center is to supply power to the motor 84. The tube 70 passing through the hollow center is to supply liquid carbon dioxide to the dispensers (or nozzles) 78. FIG. 6C shows the construction of hollow center motor 77. Item 110 is the stator, item 108 is the rotator and 112 are ball bearings.

DETAILED DESCRIPTION D FIG. 9, FIG. 10A, FIG. 10B and FIG. 15 The Preferred Embodiment of Marine Plantation

FIG. 9 shows an unit of the plantation tower. The signal buoy 150 which may be painted red, is so arranged (with long enough rope tired to the tower) that it is always on the sea surface to indicate the location of the plantation tower. The harvest buoy 152, which may be painted yellow, is used to indicate the readiness for harvesting when it disappears under marine water at low tide. Planting pans 170 are placed one above another to form a vertical tower. Pans are connected together around their circumferences with nylon wires 161 and ring and hook pairs 158. On tops of the pans, there are mixtures of gravel and packs of slowly releasing fertilizers for vegetables to take roots. Vegetables to be planted are fast growing kelp or sea weeds. Fertilizer mixture is enclosed in plastic bags punched with tiny holes. Each vertical connecting nylon line is enclosed with a plastic tube 156 used as the habitat for shell fish. Each plantation pan has an inflatable bottom filling with moderately compressed air through valve 171. The tower 174 height is about 100 to 150 feet tall and is anchored at the same location with a heavy weight 172. The spaces between planting pans serve as the living grounds for animals which form a food chain ranging from planktons to shrimps, to small fish and big fish.

FIG. 10A shows the top view of a seeding and harvesting boat. During seeding or harvesting, platforms 180 are in the lower-down or horizontal position. Slots 179 allow the central supporting nylon wire to go in, and holes 178 allow plantation pans to move vertically. Items 182 are hoists to move platforms 180 into horizontal (working) or vertical (retiring) position. Item 211 is the entrance to the lower floors of the boat. Items 184 are the storages of spare plantation pans. Item 186 is the tool storage. Item 188 is a pond for fish catch and 190 is the pond for shellfish catch. Item 194 is a centrifuge to remove water from the harvested kelp or sea weeds and 190 is a dryer for damp vegetable harvest.

The dried kelp or seaweed is stored temporarily at the rear deck of the boat. FIG. 10B shows the side view of a seeding-harvesting boat. The operating platforms are positioned vertically in a retired position. The storage 200 is for gravels and storage 202 is for slow-release fertilizer bags. Both 200 and 202 can be used for general storage. The lower deck of the boat also has an electric battery compartment, liquid carbon dioxide storages 206 and a fertilizer-solution storage 208.

FIG. 10C shows the seeding-harvesting boat in operation with the plantation column taking into the circular space 178 through slot 179 on each side of the boat (see FIG. 10A). Liquid carbon dioxide is dispensed under the plantation columns when the carbon dioxide content of the marine water is low. The fertilizer (like iron salt) solution is dispensed through dispenser 212 to promote the proliferation of diatoms to absorb carbon dioxide from the atmosphere. The propeller 218 is powered through a gear transmission 216 mainly by direct current from battery 204 and occasionally by a gasoline engine 214.

FIG. 15 shows the preferred arrangement of plantation columns. Two rows of plantation towers are placed closely together in order to form a continuous community for sea life. Double rows of plantation towers run from East to West to gain maximum exposure to sunshine for both side of the rows. There is a transportation area between double rows where the proliferation of diatoms is to be promoted.

DETAILED DESCRIPTION E-FIG. 11, FIG. 13 AND FIG. 14 The Preferred Embodiment of the Integation of Methane Mining, Carbon Dioxide Sequestering and Marine Plantation

These three operations of the present invention, namely, the mining of methane, the sequestering of carbon dioxide and the marine plantation are preferably operated interdependently. By their natures, these operations are mutually dependent on each other, both technically and economically. Comparing the complexity of technology of methane mining with that of carbon dioxide sequestering, the former is much more difficult than the latter, since the methane mining assembly has to reach to the bottom of the sea, which may be several miles deep; while the carbon dioxide sequester merely has to be brought down not much more than two thousand feet into the ocean. In addition, the technology of carbon dioxide sequestering has an enormous market already in existence. Therefore, the mining operation, especially during the development stage, may have to depend on the sequestering operation for financial viability. However, the sequestering operation depends on methane mining for cheap energy supply (in term of raw methane or synthetic fuels) to re-compress and re-liquefy the un-sequestered carbon dioxide. Without the marine plantation to absorb the residual liquid and dissolved carbon dioxide, the sequestering operation may suffer from leaking carbon dioxide back to the atmosphere and making marine water too acidic for diatoms to reduce their ability for absorbing carbon dioxide from the atmosphere. The seeding-harvesting boats depend on the main or mother ship, which houses the methane mining and sequestering operations, for supply of electricity, fuel and lots other things. The main ships may offer the plantation crews room, board and entertainment. The main ship's first rated weather station and frequent contact with the coast guard may give all the workers in the three operating groups a sense of security.

FIG. 11 shows the top view of a mother ship. 220 is the navigation chamber where the captain is piloting and directing other business. 224 is the entrance to the lower decks of the ship. 226 are carbon dioxide collecting domes. 228 are methane collecting domes. Around the methane domes, there are storages for chains, buckets and floats 304. 221 are the anchors.

The space between two groups of domes is occupied by other installations: 300 the synthetic liquid fuel plant, 302 the carbon dioxide recompression plant, 308 the natural gas liquefaction plant, and 306 the control board for the entire ship. The control board displays continuously all the important variables, such as the methane production rate, carbon dioxide sequestering rate as well as the conversion efficiency of carbon dioxide to its hydrates, etc. 310 is the living quarter for all the crew members including the plantation people.

FIG. 13 shows the sectional back view of the ship. 50 are methane or carbon dioxide domes. 324 are liquefied natural gas storages. 326 are liquid carbon dioxide storages. 328 are synthetic gasoline or liquid fuel storages. Items 330 are banks of electric batteries and alternating-to-direct current rectifiers. 332 is a wind power generator (may be more than one). 334 are panels for solar power generation.

FIG. 14 shows the recycling of the unconverted gaseous carbon dioxide from sequestering devices. Methane stream 336 and tail gas 338 from the synthetic fuel plant are fed into a two cycle turbine 340 to be burned. Item 340 drives the power generator which in turn drives the motor-compressor pair 344 and the un-sequestered carbon dioxide stream 350 is being compressed to a high pressure. The high pressured carbon dioxide condenses to a liquid in the cooler 346 and is stored in 326 or is being recycled back as stream 348 for sequestering.

DETAILED DESCRIPTION F FIG. 4, FIG. 4A, FIG. 5A, FIG. 5B, FIG. 7A, FIG. 7B, FIG. 8A, FIG. 8B, FIG. 8C, FIG. 8D, FIG. 8E and FIG. 12 Methane Mining Operation

Mining of methane from its hydrates starts with the reviewing of seismographic maps (the existing or refined ones) and work begins at a location where the methane hydrate concentration is the highest and the formation is the thickest, and the depth of the sea is the shallowest (measured by a sounder). Once the ship is on the selected location, the preparation work shall be done. As indicated by FIG. 4, at the beginning, the methane collecting dome 50 is full of air at atmospheric pressure, and the water level in the dome is the same as the sea level outside the ship, where the workers can freely do preparation and repairing tasks. Before mining, the whole body of the mining assembly is above the sea level and is exposed in the air. Under this condition, before the commencement of mining, the whole assembly can be cleaned (with jets of sea water) and carefully inspected and repaired. Each of the main drum 10 and the auxiliary drum 12 is driven, clockwise or count-clockwise, by a motor (not seen in the figure). The auxiliary drum 12 is provided to help the lengthening and shortening of the chain loops. The diameter of drum 12 is smaller than that of drum 10. During chain length change, drum 12 moves underneath drum 10 with the pins or sprockets 19 on drum 12 engaging into the holes of chain elements of the right side of the loop. See FIG. 4A. When the left side of the chain loop is supported by the sprockets 20 on drum 10 and the right side of the chain loop supported by drum 12, then the section of the right loop between 10 and 12 can be disconnected into terminals A1 and B1. The terminal A2 of the chain section to be inserted is connected with A1, another end of the chain section to be inserted, B2, is connected to B1 (see FIG. 8B). Then drum 12 moves down vertically until the newly inserted chain section is under tension. At this moment, drum 12 is disengaged from the right side of the chain loops, and a proper number of buckets together with floats are attached to the newly inserted section of chain. This process is repeated until the grinder reaches the bottom of sea. Before the mining operation started, air is pumped out and marine water is raised to the top of the dome. Pure methane is admitted into the dome until the water level in the dome equal to that of the sea level, such that the pressure inside is one atmosphere. Before the grinder begins to rotate, the walking device is put into the retiring position (see FIG. 7A), and four pegs are driven down to the methane hydrate formation to prevent the twisting of the chain loops 18 caused by the rotating motion of grinder 28 and stirrer 24. They are rotating at the opposite directions to minimize the torque existing on the chain loops.

During mining, drum 10 rotates clockwise and the rear chain loops move downward, and the forward chain loops move upward, together with the buckets hanging on them (see FIG. 4). When the empty bucket 16 passes through the bottom of mining assembly 22, it collects the paste like methane-hydrate-mud mixture, sent up by the stirrer 24. Then the chain loops carrying the hydrate-mud mixture in buckets move upward toward the surface. When the water pressure is low enough and its temperature is high enough, the methane hydrates start to decompose to methane and water. The decomposition of methane-hydrates completes when the bucket passes over the top of drum 10. Since the mining assembly is suspended over the rotating chain loops, through a group of rollers (see FIG. 5A and FIG. 5B), the mining assembly always stays at the bottom of the sea, doing its job. The mining is continuous and methane is produced non-stop. The production rate is proportional to the size of capacity of the bucket, the rotating speed of the chain-loops, and inversely proportional to the distance between adjacent buckets. When one spot is exhausted of methane hydrates, the four pegs at the bottom of sea are raised from the formation and the walking device 124 is put into working position (see FIG. 7B), the mining assembly is transported to a new site. These maneuvers are remotely controlled from the control board on the mother ship. The whole mining equipment is supported on drum, 10, which in turn rests on a hydraulic system (see FIG. 8E).

In order for the mining assembly to work smoothly, the chain loops must be taut all the time. To achieve this, an automatic tension control system is introduced as shown in FIG. 12. The tension indicator 320 is inserted between the mining assembly and the body of the ship. When a positive deviation, +e, is detected, the tension controller 322, sends a signal to the pump 146, to instruct it to remove same hydraulic fluid from the cylinder 140 to the reservoir 144, and drum 10, is lowered down accordingly and the tension is returned to the required value. When a negative error, −e, is found, the flow of the fluid is reversed. In this manner, the methane mining assembly is operated smoothly and in synchronization with the daily tide movement.

During normal production, the methane collecting dome 50 is full of methane. Any minor repair and lengthening and shortening of chain loops should be done by workers outside of the dome with the help of the transparent windows 40 and the rubber gloves 38 (see FIG. 4). There is a flow meter located on the pipe line at the exit of methane dome to measure the methane production rate and the sum of the quantity mined. After purification, the methane is divided into stream 42 and 44. Stream 42 is sent to liquefied natural gas plant 302 and stream 44 is sent to liquid fuel synthesis plant 300 (see FIG. 11).

DETAILED DESCRIPTION G FIG. 6, FIG. 6A, FIG. 6B, FIG. 6C and FIG. 6D, FIG. 6E, FIG. 6F Carbon Dioxide Sequestering Operation

The selection of the site for carbon dioxide sequestering is not as critical as that for methane mining. Anywhere methane hydrates exist, the water will be deep enough to sequester carbon dioxide. In another words, mining of methane and sequestering carbon dioxide can be operated at the same location and from the same ship. FIG. 6, FIG. 6A, FIG. 6B, FIG. 6C, FIG. 6D and FIG. 6E show the details of the sequestering operation.

A cord 66 includes (1) an electric cable to supply electricity to the motors in the sequester 86, (2) a stainless steel chain to support the weight of the sequestering device 86, and (3) a concentric flexible tube 70 to transport liquid carbon dioxide to the sequestering device and to return the expanded carbon dioxide gas back to the ship for re-compression. Cord 66 may run up to two thousand feet or more long and is wound up on a hoisting drum 64 which is driven by a motor (not shown in any figure). When the drum 64 drives clockwise, it lifts up the sequestering device 86 higher, while it rotates counter-clockwise, the sequestering device will move deeper into the marine water.

At the beginning, the dome is filled with one atmospheric pressure air and crew members can work there freely to make inspection and repairs.

Before starting sequestering, air is pumped out through line 101, and the dome is filled with pure carbon dioxide from line 105 to one atmospheric pressure. Drum 64 turns counter-clockwise, unwinding cord 66 and lowering the sequestering device 86 into the sea to a required depth. Liquid carbon dioxide comes from the central space 104 of the concentric tube 70 (see FIG. 6B), and enters the valve box 74 where it splits into two streams 96 and 98 (see FIG. 6A). They are controlled by temperature controllers 114 and 115 respectively to prevent the streams from becoming solid and interrupting the operation. Stream 96 comes out of the connection tube 71, as carbon dioxide jets 78, both above and underneath the refrigerating radiator 80. Another stream 98, serving as a refrigerant, goes into radiator 80.

The liquid carbon dioxide, as a refrigerant, expands to a gaseous carbon dioxide in the radiator through the entrance 90 (see FIG. 6D). From there, the carbon dioxide diffuses to the upper chamber of the radiator through orifices 92 and leaves the radiator through exit 88. Fins 94 improve heat transfer. The carbon dioxide leaving the radiator from 88 is led to the annular space 106 (see FIG. 6B) and back to the ship for reprocessing. Two stirrers 76 and 82 rotate at opposite directions. Stirrer 76 is pushing the carbon dioxide droplets against the upper surface of the radiator; while stirrer 82 is pushing them against the lower surface of the radiator. Motor 77 driving stirrer 76 has a hollow center as shown in FIG. 6C. The cord 66 which consists of the chain 69, the electric cable 68 and the concentric tube 70 is passing through the center of the motor. Item 110 is the stator, and item 108 the rotator of the motor, and 112 are the ball bearings. The sequestering operation is a continuous one, and its conversion efficiency can be calculated by measuring the flow rate of carbon dioxide through 96 (see FIG. 6A), and that through pipe line 101 at the top of carbon dioxide collecting dome (see FIG. 6). Both of the flow meters are not shown. The application of refrigeration is optional; however, it helps to increase the flexibility and efficiency of the sequestering operation.

Part of the un-sequestered carbon dioxide leaves the sequestering device 86 in form of gas and they bubble up underneath the ship and finally they are collected in the dome; but the remainder stays in the marine water partly as liquid and partly as soluble carbon dioxide. The unsequestered and uncollected carbon dioxide can be removed by the marine plantation or otherwise they may pose a danger of leaking as a green house gas to the environment or making marine water too acidic and harm the beneficial marine creatures, such as diatoms.

DETAILED DESCRIPTION H FIG. 9, FIG. 10A, FIG. 10B, FIG. 10 C. and FIG. 15 The Operation of Marine Plantation

The marine plantation should be a well planned operation and it is scheduled well ahead so that during sequestering of carbon dioxide, the fast growing kelp or seaweed has started to grow and is ready to absorb the unconverted carbon dioxide residues. The fundamental unit of marine plantation is a plantation unit as shown by FIG. 9. It is a group of 10 to 13 planting pans placed one above another, totaling 130 feet in height. Each pan is fixed on a nylon cord, 154 with a series of nylon wires 156. Each pan has an inflatable bottom 170 which can be filled with compressed air, through a valve 171, to support the weight of the contents of the pan. The adjacent two pans are connected together with a group of vertical nylon wires 161 located along their circumference. At the top of each vertical wire, there is a ring and hook 158 to facilitate the installation and dismembering of the plantation unit (or tower). Outside each vertical connecting nylon wire, there is a 1½-2 inch plastic tube 160 to serve as the habitat for shell fish. Each pan is filled with gravels, which is mixed with bags of slow diffusion fertilizer mixtures, for fast growing vegetables to hold their roots. On top of each plantation unit, there is a red colored balloon or buoy 150 constantly present to indicate the location of the unit. On top of the plantation column there is another yellow colored, balloon shaped buoy 152. If it submerges into the water, it is time for harvesting.

FIG. 15 indicates that two rows of plantation units are closely packed together and they run from West to East in order for the plants to get maximum exposure to the sun shine. There is a space at least 20 ft. wide between two double rows to allow the passage of the seeding-harvesting boat and letting diatoms to proliferate there.

Plantation units are served by a fleet of seeding-harvesting boats. The top view of the boat is shown in FIG. 10A, and side view in FIG. 10B.

FIG. 10A and FIG. 1C show the boat handling its seeding and harvesting jobs. When the working platform is lying horizontally, a plantation unit is handled by the hoist 182, and is brought into the space 178 through the slot 179. At the very beginning, when the plantation unit is in the circular space, all the planting pans are empty. Starting with the lowest pan, its bottom is filled with compressed air, its top is filled with broken stones and bags of slow releasing fertilizer, then at this moment, seeds of plants to be grown are released, and various fish and young shellfish are discharged. The planting pan finished with seeding is lowered down to the sea, and the next empty pan above it is lowered to the same level as the working platform, and the same seeding process is repeated until the top planting pan on the plantation unit is completed with the same procedure. Finally, the whole properly seeded plantation unit is removed from the circular space 178, by passing the main nylon cord through the slot 179, to the sea with the hoist 182.

During harvesting, the whole unit is moved into the space 178 through slot 179 by the hoist. First, the grown vegetables are harvested, then the fish are caught and are placed in the fish pond 188, and the shell fish are collected from the plastic pipes and they are stored in pond 190. The harvested plants are centrifuged in 194, and dried in 196. The dried vegetables are stored at area 198 and are later transferred to power plant to be burned to generate electricity and the ashes are leached to recover its fertilizer content. For each pan, harvesting is immediately followed by reseeding. The work starts from the top pan and ends with the bottom pan. Finally the reseeded plantation unit is removed from the circular space 178, by passing the main nylon cord through slot 179 with the help of hoist 182 to the sea.

All the boats are propelled by electric batteries which are charged from time to time at the mother ship, aiming to have a silent operation without disturbance to the living animals in the plantation community. They use gasoline propulsion only when their batteries are exhausted.

The carbon dioxide content and acidity of the marine water surrounding the marine plantation are frequently measured by the most sensitive instruments available in the market. When it is necessary, carbon dioxide is dispensed from 210, and fertilizer solution is dispensed from 212 (see FIG. 10C).

A plantation crew can help proliferating diatoms by adjusting marine water to a right acidity and supplying them with adequate nutrition such as iron. When the area of the plantation is huge, the carbon dioxide absorbed by planted vegetables and the surrounding diatoms could be colossal. At present, the diatoms absorb about one quarter of the carbon dioxide from the atmosphere, and the rest is taken up by land forests. The latter is diminishing in quantity due to land development. If the marine plantation suggested by the present invention were well developed, someday, the combined uptake of carbon dioxide by marine plantation and diatoms would surpass land forests as the number one carbon absorber!

Since the uptake of carbon dioxide by diatoms provides a valuable service to the whole mankind, the cost of its proliferation should be subsidized by United Nation, and likewise, this operation should be under its supervision.

In this patent application, there are several alternative embodiments:

1. The body of the collecting domes can be of any other forms than a cylinder, a square, etc. and their tops can a cones or any thing else.

2. The number of chain loops to lift methane hydrates to the sea surface can be one, two or more.

3. When no refrigeration is employed in the sequestering, there is only one ordinary tube to transfer carbon dioxide from the ship to the sequestering device.

4. All the methane collecting domes can be grouped together with only one outside wall in the shape of a circle, rectangle, square, or oval. There is no wall between individual domes.

5. The same embodiment in 4 can be applied to carbon dioxide collecting domes.

6. The number of chain loop to rotate the methane-hydrates-collecting buckets can be one or any number more than two.

Although the features in the present invention are unobvious to those who are in the trade, the development and construction of the ship for methane mining and carbon dioxide sequestering still depends upon the knowledge of conventional ship building, such as the stress analysis and the safety assessment.

The successful development and large scale implementation of methane mining from its hydrates, suggested by the present invention, has the potential of making ocean neighboring countries, such as United States of America, Japan, China, Taiwan and India, energy independent. World's decreasing dependence on Mid-East's oil could bring political stability and peace to this region.

The carbon-dioxide-sequestering technique together with the marine plantation should be first applied to coal-burning power plants and Canada's oil-sand refineries. The world's emission of carbon dioxide is about 29 billon tons annually of which about 11 billion tons are from burning coal in U.S. and China. Coal is the cheapest fuel for power generation. The world can't afford to not use it, and its use is increasing in developing countries such as China and India. The fact that extraction of petroleum from Canada's oil sand emits large quantity of carbon dioxide limits the production capacity of oil-sand petroleum to the present rate of about 2 million tons a day, the methods of the present invention could lift this restriction and the production rate of Canadian-oil-sand based petroleum could be increased to 10 times of that in a short period of time. The capturing and sequestering of carbon dioxide from those two big polluters could eliminate about 40% of total greenhouse gas emission, and it might be possible that the goal of achieving 50% reduction in the year 2050 expressed by recent G-8 Meeting in Germany could be realized decades earlier.

The marine plantation suggested by the present invention not only could prevent the marine-water pollution due to carbon-dioxide sequestering but when the operation is of a very large scale it could also produce an enormous quantity of bio-fuel and profusion of less-polluted-salt-water fish, which at present is near extinction due to over fishing. Since the job of proliferation of diatoms can be a part-time assignment for the plantation crew, its cost would be much less than that of companies undertaking it as their sole duty.

If the oceanic exploitation suggested by the present invention were well developed and widely implemented, the world's economy may switch gradually from being a petroleum based to one that is ocean based.

REFERENCES

-   1. Komai et al, Japan, Preprints Division of Fuel Chemistry, ACS     National Meeting 1997, San Francisco, pp. 568-572. -   2. Sloan, E. Dendy, Jr., “Clathrate Hydrates of Natural gases”,     Marcel Dekker, Inc., New York. -   3. Herzog et al: “Environmental Impacts of Ocean Disposal of Carbon     Dioxide”, Energy Conversions Management, Vol. 37, No. 608, pp.     99-105, 1996. -   4. Rau et al: “Enhanced Carbonate Dissolution as a Means of     Sequestering Carbon Dioxide in Ocean”, Transaction, American     Geophysical Union 81 (48), 283, Nov. 28, (2000). -   5. Baes et al, “Options for the Collection and Disposal of Carbon     Dioxide”, Oak Ridge National Laboratory Document ORNL-5657,     published May 1980. -   6. Steinberg et al, A System study for the Removal, Recovery and     Disposal of Carbon Dioxide from Fossil Fuel Power Plants in the     U.S.”, Proceedings of the Air Pollution Association, Annual Meeting,     78^(th), Vol. 3, pp. 4-24 (1985). -   7. Herzog, “Ocean Sequestration of Carbon Dioxide—An Overview”,     Fourth International Conference on Greenhouse Gas Control     Technologies, pp. 1-7, (Aug. 30-Sep. 2, 1998). -   8. Morgan et al, “Hydrate Formation from Carbon Dioxide and Water”,     Environ. Sci. Technol., vol. 33, pp. 1448-1452 (1999). -   9. Hirai et al, “Advanced Carbon Dioxide Dissolution Technology for     Longer Term Sequestration with Minimum Biological Impacts”,     Greenhouse Gas Control Technologies”, Elsevier Science, Ltd, pp.     317-322 (1999). -   10. Yamasaki et al, “A new Ocean Disposal Scenario for anthropogenic     Carbon Dioxide: Carbon Dioxide Hydrate Formation in A Submerged     Crystallizer and Its Disposal”, Energy, pp. 85-90, vol. 25 (2000). -   11. Suess et al, “Flammable Ice”, Scientific America, No. 99, Vol.     281, Issue 5, pp. 76. -   12. Ballard A. L., et al: Hydrate Phase Diagrams for     Methane+Ethane+Propane Mixture, Chemical Engineering Science, Vol.     56 (2001), pp. 6883-6895. -   13. Austivak et al, “Deposition of Carbon dioxide on the Seabed in     the Form of Hydrates”, Energy Conversions Management, Vol. 33     (1992), No. 5-8, pp. 650-666. -   14. Jones, Ian S. F. et al, “Enhanced Carbon Dioxide by the World's     Oceans”, Energy Conversions Manage., 37 (6-8), pp. 1049-1052 (1996). -   15. Tanaka, S., “Possible Contribution of Carbon Dioxide Flooding to     Global Environment Issues, Energy Conversions Management. No. 5-8,     pp. 587-593. 

1.-16. (canceled)
 17. A method of exploiting an ocean and its bottom, said method comprising: (a) mining methane from a methane hydrate formation at said ocean bottom; (b) combusting at least a portion of said methane to sequester carbon dioxide at said ocean bottom, and (c) absorbing by a marine plantation unit at least a portion of any residual carbon dioxide not sequestered.
 18. The method of claim 17, further comprising proliferating diatoms in ocean water of said plantation unit.
 19. The method of claim 17, wherein said sequestering comprises: i) bringing carbon dioxide down to a depth in said ocean having a pressure high enough and a temperature low enough to convert said carbon dioxide gas to carbon dioxide hydrates; ii) sequestering said carbon dioxide hydrates in a sequestering region at the bottom of said ocean; and iii) collecting above the surface of the ocean carbon dioxide gas that has not been converted to carbon dioxide hydrates.
 20. A method of mining methane from a methane-hydrate formation at an ocean bottom said method comprising: (a) grinding said methane-hydrates together with inert mass from said ocean bottom into a paste, (b) bringing the paste up to the surface of the ocean, (c) decomposing the methane hydrates on their way up to the ocean surface, (d) collecting the decomposed methane above the ocean surface.
 21. The method of claim 20 wherein the paste is brought to the ocean surface in buckets hanging on moving chain loops, wherein the said chain loops are driven by sprockets on a drum.
 22. The method of claim 21, wherein the said drum is supported on a hydraulic system which is regulated by a tension controller.
 23. The method according to claim 22, wherein vertical movement of the drum is synchronized with tide movement by an automatic stress controller.
 24. The method of claim 20, wherein the said grinding is performed by a mining assembly suspended on chain loops through a pair of rollers and channel, wherein when the chain loops are rotating, the mining device continues grinding without changing its location.
 25. The method of claim 21, further comprising supporting said chains, buckets, said paste by attaching buoys to said buckets.
 26. The method of claim 20, wherein said decomposed methane is collected above the ocean surface into a dome.
 27. The method of claim 26, wherein the dome comprises transparent windows and gloves attached to said windows to allow workers outside the dome to use, repair and adjust machinery inside the dome.
 28. The method of claim 27, wherein the mining device further comprises a walking device.
 29. A method of sequestering carbon dioxide at an ocean bottom, said method comprising: (a) bringing carbon dioxide down to a depth in an ocean, said depth having a pressure high enough and a temperature low enough to convert said carbon dioxide gas to carbon dioxide hydrates; (b) sequestering said carbon dioxide hydrates in a sequestering region at the ocean bottom; (c) collecting above the surface of the ocean carbon dioxide gas that has not been converted to carbon dioxide hydrates, and (d) absorbing by a marine plantation in said sequestering region at least a portion of any residual carbon dioxide not sequestered or collected.
 30. The method of claim 29, further comprising dispersing liquid carbon dioxide into droplets and depositing said droplets in said sequestering region.
 31. The method of claim 30, further comprising cooling said sequestering region by expanding a portion of said liquid carbon dioxide into a vapor in a radiator in contact with ocean water located at said sequestering region.
 32. A method of marine farming comprising: (a) cultivating plants in a plantation unit in ocean water by means of a seeding and harvesting boat and its crew in said ocean above said plantation unit, and (b) proliferating diatoms in ocean water of said plantation unit, wherein said proliferating is by means of said seeding and harvesting boat.
 33. The method of claim 32, wherein the said plantation unit comprises a plurality of planting pans.
 34. The method of claim 33, wherein said planting pans are stacked vertically and connect to a cord.
 35. The method of claim 34, wherein said cord is anchored to the bottom of the ocean.
 36. The method of claim 32, wherein a plurality of said plantation units run from west to east to maximize sunshine exposure.
 37. The method of claim 33 wherein the said planting pans further comprise fertilizer bags to increase growth of said plants.
 38. The method of claim 32, further comprising harvesting said plants and centrifugally removing water from said harvested plants.
 39. The method of claim 32, wherein said seeding and harvesting boat comprises an enclosure having a slot through which the plantation unit enters, and said boat further comprises a centrifuge for removing water from harvested plants. 